Given the criterion of assessment precision, an approach using multiple methods is recommended (Nunnally, 1978). One common solution is a multi-trait, multi-method (MTMM) approach, where different attributes are measured using multiple methods, typically organized in a matrix (Campbell & Fiske, 1959). The key assumption is that each assessment method will contain some error or bias and by combining multiple methods, a more precise and reliable overall measure will be generated (Church & Rotolo, 2013). This begs the question of how to combine data from different methods in order to inform selection decisions or development planning (Ryan & Ployhart, 2014), which is a topic under discussion and evolution in the area of assessment and measurement.
Balanced against the need for a precise and rigorous measure is the consideration of how acceptable the assessment experience will be to the leader audience. Especially for leaders in the organization, as opposed to a candidate for an entry-level position, the effect of the assessment is important. Not only are leaders often very busy - and typically ambitious and successful - but they may also wield substantial power in the organization. This can result in considerable resistance on their part to the time required to complete an extensive series of assessments on multiple attributes (Howard & Thomas, 2010). As a result, it is important to be cognizant of face validity (i.e., the individual should be able easily to see and understand the relevance of the assessments to their role as a leader). It is equally important that relevant and useful feedback is provided, which is seen as and easily translatable into action.
As part of our section on how to determine which assessments to use, we have discussed the importance of specific criteria for leadership development, have reviewed a number of relatively common assessment types and have discussed the importance of using multiple methods and combining data - all with the underlying goal of assessing the appropriate attributes in the most acceptable way possible. When deciding which assessments to use, it is vital that the decision is based on an understanding of the assessment purpose and what specific attributes need to be assessed. Beyond that, there is the consideration of how to maximize precision while balancing acceptability to the unique demands of the leader audience.